The present invention relates to a multidirectional input device and an electronic apparatus using the same. The multidirectional input device is used for inputting and controlling of an electronic apparatus, e.g., a cellular phone, an information terminal, a game apparatus and a remote controller.
A conventional multidirectional input device disclosed in Japanese Patent Application Non-Examined Publication No. H10-125180 is described hereinafter with reference to FIGS. 36, 37 and 38. FIG. 36 shows a sectional view of a multidirectional control switch as an electronic component used in a multidirectional input device, and FIG. 37 shows an exploded perspective view of the switch. In FIGS. 36, 37 and 38, domed contact 2 made of thin elastic metal plate is placed in a center of box-shaped casing 1 made of insulated resin. Four outer fixed contacts 3 conduct each other and are placed on inner bottom of box-shaped casing 1. A rim of domed moving contact 2 rests on outer fixed contacts 3. Independent four inner-fixed contacts 4 (4A, 4B, 4C, 4D) are located inside of outer fixed contacts 3. Four inner-fixed contacts 4 are equidistant and equiangular from a center of domed moving contact 2. Output terminals (not shown) conducted to respective contacts 4 electrically are located outside of box-shaped casing 1.
An opening of top surface of box-shaped casing 1 is covered with cover 5. Operating section 6 is formed of frame 6A and flange 6B. Flange 6B is incorporated beneath frame 6A. Frame 6A protrudes from through-hole 5A, which is punched at the center of cover 5. Flange 6B does not rotate but can tilt, because perimeter of flange 6B is mated with inner wall 1A of box-shaped casing 1. Flange 6B has four pressing sections 7 (7A, 7B, 7C, 7D, (7D is not shown)) corresponding to four inner-fixed contacts 4 (4A, 4B, 4C, 4D) beneath its lower surface. Four pressing sections 7 come in contact with upper surfaces of domed moving contact 2, and an upper surface of flange 6B is pressed by a lower surface of cover 5. As a result, operating section 6 stands vertically to a bottom of box-shaped casing 1 and takes a neutral position (hereinafter it is called vertical-neutral position).
As shown with an arrow mark in FIG. 38, when upper left side of knob 8 put on frame 6A is pressed, operating section 6 is fulcrumed at upper right side of flange 6B and tilts from the vertical-neutral position of FIG. 36. Pressing sections 7A presses domed moving contact 2, so that a part of contact 2 bows downward resiliently. Domed moving contact 2 comes in contact with inner-fixed contact 4A, and contact 4A shorts with outer fixed contacts 3. As a result, the multidirectional control switch is turned ON and an electric signal is supplied to outside via respective output terminals. When pressure of knob 8 is removed, operating section 6 returns to the original vertical-neutral position by elastic restoring force of domed moving contact 2. Outer fixed contacts 3 and inner-fixed contact 4A are separated and the multidirectional control switch is turned OFF.
A multidirectional device using the multidirectional control switch supplies an electric signal to a microprocessor for calculation, thereby recognizing an input direction and outputting a signal responsive to the direction, where the electric signal shows which of inner-fixed contacts 4 is connected to outer fixed contacts 3.
In the conventional multidirectional control switch, the number of directions can be input (resolution of input directions) depends on the number of inner-fixed contacts 4. Because domed moving contact 2 bows downward resiliently and comes in contact with contacts 4 when operating section 6 is tilted by knob 8. Since an electronic apparatus becomes downsized recently, electronic components used in the apparatus are required to be smaller. The conventional switch is difficult to increase the number of inner-fixed contacts 4 more than four, because the component should be smaller and a high resolution as well as stable operation is required.
Resolution of eight directions is obtainable as follows. Operating section 6 tilts toward the middle between inner-fixed contacts 4, and both of adjacent contacts 4 become simultaneously ON within a given time. Switch-recognizing means for recognizing simultaneous ON state is formed of a microprocessor and recognizes the difference between the simultaneous ON state and an individual ON state by respective four inner-fixed contacts 4 as a different signal. In this case, resolution of eight directions is obtained, but this is the maximum resolution by the conventional method.
The present invention addresses the problem discussed above, and aims to provide a multidirectional input device and an electronic apparatus using the same. The multidirectional input device can be small enough to be used in an apparatus downsized recently and has a high resolution of input direction.
The multidirectional input device of this invention includes the following elements:
(a) a ring-shaped resistance element layer formed on an insulating substrate,
(b) a conductive section disposed on a plane substrate which is spaced from said resistance element layer at a given insulating space, and
(c) an operating section for bringing the resistance element layer into contact with the conductive section partially.
When the insulating substrate or the plane substrate is pressed using the operating section, the resistance element layer comes in contact with the conductive section partially. If a given voltage is applied to the resistance element layer at that time, the multidirectional input device can detect the contacted position using a signal obtained at the conductive section.